1use std::{
2 ffi::{CStr, CString},
3 fmt, io,
4 ops::Deref,
5 path::Path,
6};
7
8use skia_bindings::{self as sb, SkData};
9
10use crate::{interop::RustStream, prelude::*};
11
12pub type Data = RCHandle<SkData>;
13unsafe_send_sync!(Data);
14require_base_type!(SkData, sb::SkNVRefCnt);
15
16impl NativeRefCounted for SkData {
17 fn _ref(&self) {
18 unsafe { sb::C_SkData_ref(self) }
19 }
20
21 fn _unref(&self) {
22 unsafe { sb::C_SkData_unref(self) }
23 }
24
25 fn unique(&self) -> bool {
26 unsafe { sb::C_SkData_unique(self) }
27 }
28}
29
30impl Deref for Data {
31 type Target = [u8];
32 fn deref(&self) -> &Self::Target {
33 self.as_bytes()
34 }
35}
36
37impl PartialEq for Data {
38 // Although there is an implementation in SkData for equality testing, we
39 // prefer to stay on the Rust side for that.
40 fn eq(&self, other: &Self) -> bool {
41 self.deref() == other.deref()
42 }
43}
44
45impl fmt::Debug for Data {
46 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
47 f.debug_struct("Data").field(name:"size", &self.size()).finish()
48 }
49}
50
51impl Data {
52 pub fn size(&self) -> usize {
53 self.native().fSize
54 }
55
56 pub fn is_empty(&self) -> bool {
57 self.size() == 0
58 }
59
60 pub fn as_bytes(&self) -> &[u8] {
61 unsafe { safer::from_raw_parts(self.native().fPtr as _, self.size()) }
62 }
63
64 // TODO:
65 // pub unsafe fn writable_data(&mut self) -> &mut [u8]
66
67 pub fn copy_range(&self, offset: usize, buffer: &mut [u8]) -> &Self {
68 buffer.copy_from_slice(&self.as_bytes()[offset..offset + buffer.len()]);
69 self
70 }
71
72 // TODO: rename to copy_from() ? or from_bytes()?
73 pub fn new_copy(data: &[u8]) -> Self {
74 Data::from_ptr(unsafe { sb::C_SkData_MakeWithCopy(data.as_ptr() as _, data.len()) })
75 .unwrap()
76 }
77
78 /// Constructs Data from a given byte slice without copying it.
79 ///
80 /// Users must make sure that the underlying slice will outlive the lifetime of the Data.
81 #[allow(clippy::missing_safety_doc)]
82 pub unsafe fn new_bytes(data: &[u8]) -> Self {
83 Data::from_ptr(sb::C_SkData_MakeWithoutCopy(data.as_ptr() as _, data.len())).unwrap()
84 }
85
86 #[allow(clippy::missing_safety_doc)]
87 pub unsafe fn new_uninitialized(length: usize) -> Data {
88 Data::from_ptr(sb::C_SkData_MakeUninitialized(length)).unwrap()
89 }
90
91 pub fn new_zero_initialized(length: usize) -> Data {
92 Data::from_ptr(unsafe { sb::C_SkData_MakeZeroInitialized(length) }).unwrap()
93 }
94
95 // TODO: use Range as stand in for offset / length?
96 pub fn new_subset(data: &Data, offset: usize, length: usize) -> Data {
97 Data::from_ptr(unsafe { sb::C_SkData_MakeSubset(data.native(), offset, length) }).unwrap()
98 }
99
100 /// Constructs Data from a copy of a &str.
101 ///
102 /// Functions that use `Data` as a string container usually expect it to contain a c-string
103 /// including the terminating 0 byte, so this function converts the Rust `str` to a `CString`
104 /// and calls [`Self::new_cstr()`].
105 pub fn new_str(str: impl AsRef<str>) -> Data {
106 Self::new_cstr(&CString::new(str.as_ref()).unwrap())
107 }
108
109 /// Constructs Data from a &CStr by copying its contents.
110 pub fn new_cstr(cstr: &CStr) -> Data {
111 Data::from_ptr(unsafe { sb::C_SkData_MakeWithCString(cstr.as_ptr()) }).unwrap()
112 }
113
114 /// Create a new `Data` referencing the file with the specified path. If the file cannot be
115 /// opened, the path contains 0 bytes, or the path is not valid UTF-8, this returns `None`.
116 ///
117 /// This function opens the file as a memory mapped file for the lifetime of `Data` returned.
118 pub fn from_filename(path: impl AsRef<Path>) -> Option<Self> {
119 let path = CString::new(path.as_ref().to_str()?).ok()?;
120 Data::from_ptr(unsafe { sb::C_SkData_MakeFromFileName(path.as_ptr()) })
121 }
122
123 // TODO: MakeFromFile (is there a way to wrap this safely?)
124
125 /// Attempt to read size bytes into a [`Data`]. If the read succeeds, return the data,
126 /// else return `None`. Either way the stream's cursor may have been changed as a result
127 /// of calling read().
128 pub fn from_stream(mut stream: impl io::Read, size: usize) -> Option<Self> {
129 let mut stream = RustStream::new(&mut stream);
130 Data::from_ptr(unsafe { sb::C_SkData_MakeFromStream(stream.stream_mut(), size) })
131 }
132
133 pub fn new_empty() -> Self {
134 Data::from_ptr(unsafe { sb::C_SkData_MakeEmpty() }).unwrap()
135 }
136}
137
138#[cfg(test)]
139mod tests {
140 use super::*;
141
142 impl RefCount for SkData {
143 fn ref_cnt(&self) -> usize {
144 self._base.ref_cnt()
145 }
146 }
147
148 #[test]
149 fn data_supports_equals() {
150 let x: &[u8] = &[1u8, 2u8, 3u8];
151 let d1 = Data::new_copy(x);
152 let d2 = Data::new_copy(x);
153 assert!(d1 == d2)
154 }
155
156 #[test]
157 fn from_stream_empty() {
158 let data = [];
159 let cursor = io::Cursor::new(data);
160 let data = Data::from_stream(cursor, 0).unwrap();
161 assert_eq!(data.len(), 0);
162 }
163
164 #[test]
165 fn from_stream() {
166 let data = [1u8];
167 let cursor = io::Cursor::new(data);
168 let data = Data::from_stream(cursor, 1).unwrap();
169 assert_eq!(data.len(), 1);
170 assert_eq!(data[0], 1u8);
171 }
172}
173